CRACK OTL - Issues After First POWER ON [resolved]

mipheres · 6027

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Offline Paul Birkeland

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Reply #15 on: September 28, 2016, 08:26:59 PM
Check your solder joint that connects A4 and A5.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline mipheres

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Reply #16 on: October 01, 2016, 10:14:34 PM
Hi,

As you can see A4-A5 are ok.

the reading from Terminals:
1-140v
2-160v
3-0
4-160v
5-80v

Also, the second led does not glow.




Offline Paul Birkeland

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Reply #17 on: October 02, 2016, 06:32:48 AM
Inside the 12AU7 are two vertical plate structures.  Can you see little glowing dots and the top and/or bottom of each of these structures while the amp is running?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline mipheres

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Reply #18 on: October 06, 2016, 04:36:49 AM
no , I dont see the small tube glow.
The bigger tube is working.



Offline Deluk

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Reply #19 on: October 07, 2016, 01:40:19 AM
Make sure the unlit led is soldered to the central pin. It looks a bit suspect there. Small tube glow varies. Some hardly glow at all and only show when its dark.



Offline mipheres

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Reply #20 on: October 18, 2016, 08:11:12 PM
Hi I made sure the led is soldered ok.

Still same result,
the voltage measurements are off
small tube does not glow
one of the leds does not lit.




Offline Deluk

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Reply #21 on: October 19, 2016, 01:53:49 AM
Looks as if you have a link between A1 and A2. This shouldn't be there.



Offline mipheres

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Reply #22 on: October 30, 2016, 09:51:22 PM
triple checked A1-A2 connection, Nothing there: A1 is not connected to A2.

What should I check next?



Offline Deluk

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Reply #23 on: October 31, 2016, 02:30:52 AM
triple checked A1-A2 connection, Nothing there: A1 is not connected to A2.

Just looked at your picture again and have to say that I'm very surprised at that. What do others think?




Offline kgoss

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Reply #24 on: October 31, 2016, 03:25:27 AM
The picture looks like maybe a resistor lead that you clipped is shorting the pins?  The wire looks a lot smaller than the coated wire.

Ken Goss


Offline ALL212

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Online Doc B.

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Reply #26 on: October 31, 2016, 11:23:12 AM
Witch LED are you referring too?

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline borism

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Reply #27 on: October 31, 2016, 12:44:27 PM
Of the WEST!

Boris


Offline ALL212

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Reply #28 on: November 01, 2016, 01:23:37 PM
Since I'm feeling guilty about derailing this a bit...

I've blown boards and "other" with cutoffs falling into places you really don't want them to fall.  Based on the picture you may have a cutoff that has dropped into the socket area.  Toothbrush works good for sweeping in areas like that.  I have to use a magnifying glass to get in that close but it works.

Aaron Luebke


Offline mipheres

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Reply #29 on: November 02, 2016, 09:07:38 PM
you are right about the clipping, but when I wrote "triple check", this was after  I cleared the metal and checked for a short with a tester.

witch way to go now? "go west"? ;D